тныхх 3.
a1=-3
1) = -6log(x)-cosx(x) + константа
SinA-Sin3A 1/2 - 3*(1/2) 1/2 - 3/2 -2/2
--------------- = ---------------- = ------------- = -------- = -0,5 - Решение
Sin4A 4*(1/2) 4/2 4/2
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sinA = 1/2